1. Field of the Invention
The present invention relates to a motor vehicle, particularly a passenger vehicle. Such a vehicle comprises a passenger compartment, a bumper positioned forward thereof in the direction of travel of the vehicle, and at least one supporting and impact-resisting structure disposed between the bumper and the passenger compartment, the structure extending basically in the longitudinal direction of the vehicle and being provided with two side members disposed at the height of the bumper, supporting it at their front end, and extending basically in the longitudinal direction of the vehicle toward the passenger compartment.
2. Discussion of the Background
Numerous proposals already have been made to improve safety in the event of frontal impacts between a vehicle and a fixed or movable obstacle, especially in the event of impacts between two vehicles. All proposals are aimed at absorbing the kinetic energy of the impact in more or less controlled and localized manner, at the front of the vehicle, in order to prevent irreparable harm to the passengers.
According to British Patent 1532408, kinetic-energy-absorbing devices such as hydraulic or pneumatic cylinders are interposed between the bumper and the side members. According to other proposals, diverse types of metal profiled sections are used, especially in the form of solid or hollow beams, intended to absorb the kinetic energy of the impact better and to have predictable behavior.
French Patent 2439124 describes a motor vehicle, particularly a passenger vehicle, provided with a passenger compartment, a bumper positioned forward thereof in the direction of travel of the vehicle, and at least one supporting and impact-resisting structure disposed between the bumper and the passenger compartment, the structure extending basically in the longitudinal direction of the vehicle and being provided with two upper side members disposed at the height of the bumper, supporting it at their front end, and extending basically in the longitudinal direction of the vehicle toward the passenger compartment, two lower side members disposed parallel to and underneath the upper side members and joined to the upper side members by two binding supports, a crossbeam connecting the two lower side members at their front end; the lower side members are disposed at the level of the floor of the passenger compartment and are joined thereto at their rear end; their front end is well back of the front ends of the upper side members, and is connected thereto by two sloping binding supports. In the event of an impact, it is substantially the upper side members that become deformed, the sloping binding supports being bent vertically upward during the impact; as a result, it is possible that the lower side members may undergo a certain deformation.
These known devices certainly contribute to attenuating the violence of impacts by channeling and absorbing the kinetic energy, but they do not prevent other adverse phenomena from occurring, particularly the wedging of one vehicle into the other in the case of frontal impact, with penetration of an upper side member of one vehicle into the vehicle traveling in the opposite direction. This is a major risk in particular in xe2x80x9cleft sidexe2x80x9d frontal collisions (for left-hand drives), with only 50% overlap of the vehicles. In fact, the structure disclosed by French Patent 2439124 would even have a tendency to aggravate the situation, since the upper side members are positioned in the manner of rams.
The object of the invention is to remedy this problem and to propose a vehicle comprising an impact-resisting and impact-absorbing structure, capable of limiting the risks of wedging or penetration in the event of frontal impact between two vehicles.
The invention achieves its object by virtue of a motor vehicle, particularly a passenger vehicle, provided with a passenger compartment, a bumper positioned forward thereof in the direction of travel of the vehicle, and at least one supporting and impact-resisting structure disposed between the bumper and the passenger compartment, the structure extending basically in the longitudinal direction of the vehicle and being provided with at least two upper side members disposed at the height of the bumper, supporting it at their front end, and extending basically in the longitudinal direction of the vehicle toward the passenger compartment, at least two lower side members disposed parallel to and underneath the upper side members and joined to the upper side members by two binding supports, a crossbeam connecting the two lower side members at their front end, characterized in that the front ends of the lower side members are substantially vertically aligned with the front ends of the upper side members and the binding supports are disposed substantially between the front ends of the upper and lower side members. Very advantageously, the rear end of the lower side members is disposed in such a way that it will be braced against a stop portion of the vehicle structure in the event of frontal impact.
Thus the crossbeam and the binding supports form a U-shaped frame suspended in vertical alignment with the front ends of the upper side members. This structure makes it possible, in the event of a frontal impact between two vehicles, to prevent the upper side members of one vehicle from passing above those of the vehicle traveling in the opposite direction, by virtue of the fact that the low path for transmission of forces, constituted by the U-shaped frame, can xe2x80x9cinterceptxe2x80x9d structural elements of the other vehicle, the motive power unit or the wheel. In other words, the U-shaped frame prevents the side members from rising upward during the impact.
It will be noted that, in the art of trucks, there is known from European Patent 0696535, for example, a structure in which a crossbeam provided at the front of the side members forms with the bumper a frame at the front of the vehicle, but this structure is provided substantially for mounting trailer-coupling means and does not play any part in the matter of absorbing the kinetic energy of the impact, and furthermore, it is not provided with lower side members.
Advantageously, the lower side members are entirely suspended on the upper side members, their rear ends being disposed at a distance from a stop portion of the vehicle structure, with which they make contact only in the event of an impact.
The lower side members are suspended from the upper side members not only by the binding supports but also by at least one tie rod.
Advantageously, the lower side member on the engine side is suspended by a single tie rod and the lower side member on the gearbox side is suspended by two tie rods.
The lower side members are constructed in such a way, for example in the form of hollow bodies, that they can absorb the kinetic energy of the impact. Preferably they comprise two longitudinal sections of different compressibility.
Advantageously, a restraining device without permanent contact is provided at the rear end of the lower side members to prevent them from becoming axially misaligned with the stop portion of the passenger compartment.